feat: add UI components including Skeleton, Slider, Toaster, Switch, Table, Tabs, Textarea, Toggle Group, Toggle, Tooltip, and User Avatar

- Implemented Skeleton component for loading states.
- Added Slider component using Radix UI for customizable sliders.
- Created Toaster component for notifications with theme support.
- Developed Switch component for toggle functionality.
- Introduced Table component with subcomponents for structured data display.
- Built Tabs component for tabbed navigation.
- Added Textarea component for multi-line text input.
- Implemented Toggle Group and Toggle components for grouped toggle buttons.
- Created Tooltip component for displaying additional information on hover.
- Added User Avatar component for displaying user images with fallback.
- Implemented useIsMobile hook for responsive design.
- Created API utility functions for user and thought data fetching.
- Added utility function for class name merging.
- Updated package.json with new dependencies for UI components and utilities.
- Added TypeScript configuration for path aliasing.

thoughts-frontend/components/ui/resizable.tsx

@@ -0,0 +1,56 @@
+"use client"
+
+import * as React from "react"
+import { GripVerticalIcon } from "lucide-react"
+import * as ResizablePrimitive from "react-resizable-panels"
+
+import { cn } from "@/lib/utils"
+
+function ResizablePanelGroup({
+  className,
+  ...props
+}: React.ComponentProps<typeof ResizablePrimitive.PanelGroup>) {
+  return (
+    <ResizablePrimitive.PanelGroup
+      data-slot="resizable-panel-group"
+      className={cn(
+        "flex h-full w-full data-[panel-group-direction=vertical]:flex-col",
+        className
+      )}
+      {...props}
+    />
+  )
+}
+
+function ResizablePanel({
+  ...props
+}: React.ComponentProps<typeof ResizablePrimitive.Panel>) {
+  return <ResizablePrimitive.Panel data-slot="resizable-panel" {...props} />
+}
+
+function ResizableHandle({
+  withHandle,
+  className,
+  ...props
+}: React.ComponentProps<typeof ResizablePrimitive.PanelResizeHandle> & {
+  withHandle?: boolean
+}) {
+  return (
+    <ResizablePrimitive.PanelResizeHandle
+      data-slot="resizable-handle"
+      className={cn(
+        "bg-border focus-visible:ring-ring relative flex w-px items-center justify-center after:absolute after:inset-y-0 after:left-1/2 after:w-1 after:-translate-x-1/2 focus-visible:ring-1 focus-visible:ring-offset-1 focus-visible:outline-hidden data-[panel-group-direction=vertical]:h-px data-[panel-group-direction=vertical]:w-full data-[panel-group-direction=vertical]:after:left-0 data-[panel-group-direction=vertical]:after:h-1 data-[panel-group-direction=vertical]:after:w-full data-[panel-group-direction=vertical]:after:translate-x-0 data-[panel-group-direction=vertical]:after:-translate-y-1/2 [&[data-panel-group-direction=vertical]>div]:rotate-90",
+        className
+      )}
+      {...props}
+    >
+      {withHandle && (
+        <div className="bg-border z-10 flex h-4 w-3 items-center justify-center rounded-xs border">
+          <GripVerticalIcon className="size-2.5" />
+        </div>
+      )}
+    </ResizablePrimitive.PanelResizeHandle>
+  )
+}
+
+export { ResizablePanelGroup, ResizablePanel, ResizableHandle }